DOCSLIB.ORG

Comprehensive Understanding of Hillocks and Ion Tracks in Ceramics Irradiated with Swift Heavy Ions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Comprehensive Understanding of Hillocks and Ion Tracks in Ceramics Irradiated with Swift Heavy Ions Article Comprehensive Understanding of Hillocks and Ion Tracks in Ceramics Irradiated with Swift Heavy Ions Norito Ishikawa 1,* , Tomitsugu Taguchi 2 and Hiroaki Ogawa 1 1 Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan; [email protected] 2 Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Tokai, Ibaraki 319-1106, Japan; [email protected] * Correspondence: [email protected]; Tel.: +81-29-282-6089; Fax: +81-29-282-6716 Received: 13 November 2020; Accepted: 8 December 2020; Published: 9 December 2020 Abstract: Amorphizable ceramics (LiNbO3, ZrSiO4, and Gd3Ga5O12) were irradiated with 200 MeV Au ions at an oblique incidence angle, and the as-irradiated samples were observed by transmission electron microscopy (TEM). Ion tracks in amorphizable ceramics are confirmed to be homogenous along the ion paths. Magnified TEM images show the formation of bell-shaped hillocks. The ion track diameter and hillock diameter are similar for all the amorphizable ceramics, while there is a tendency for the hillocks to be slightly bigger than the ion tracks. For SrTiO3 (STO) and 0.5 wt% niobium-doped STO (Nb-STO), whose hillock formation has not been fully explored, 200 MeV Au ion irradiation and TEM observation were also performed. The ion track diameters in these materials are found to be markedly smaller than the hillock diameters. The ion tracks in these materials exhibit inhomogeneity, which is similar to that reported for non-amorphizable ceramics. On the other hand, the hillocks appear to be amorphous, and the amorphous feature is in contrast to the crystalline feature of hillocks observed in non-amorphizable ceramics. No marked difference is recognized between the nanostructures in STO and those in Nb-STO. The material dependence of the nanostructure formation is explained in terms of the intricate recrystallization process. Keywords: swift heavy ion; hillocks; ion tracks; ion irradiation; TEM 1. Introduction Long nanometer-sized damage trails are created in ceramics continuously along the trajectories of swift heavy ions (SHIs), if the energy transfer from a SHI to an electron system of ceramics is sufficiently high [1–3]. Such characteristic damage is called an ion track. The mechanism of ion track formation has been extensively studied so far, and it has been one of the central topics in the research on ion-solid interactions. Ceramics can be categorized into two groups; amorphizable and non-amorphizable ceramics. If amorphous ion tracks are created, the ceramics are called amorphizable ceramics. The electronic stopping power dependence of ion track sizes in many amorphizable ceramics has been successfully predicted using the thermal spike model [4–8]. According to the model, the amorphous ion track formation is attributable to a local temperature rise sufficient to cause local melting along an ion path. On the other hand, there are non-amorphizable ceramics in which a crystal structure within an ion track region is not amorphized [9–14]. It has been found that in non-amorphizable ceramics, ion track size is markedly smaller than the size of the melt predicted by the thermal spike models [13,14]. Recent molecular dynamics (MD) simulation has revealed that the small ion tracks in non-amorphizable ceramics are attributable to fast recrystallization after transient melting [15–18]. It has been pointed out that the ionic nature of atomic bonding in non-amorphizable ceramics may be responsible for such fast recrystallization in non-amorphizable ceramics [9,19]. However, there is Quantum Beam Sci. 2020, 4, 43; doi:10.3390/qubs4040043 www.mdpi.com/journal/qubs Quantum Beam Sci. 2020, 4, 43 2 of 14 currently no consensus on which material property makes the distinction between amorphizable and non-amorphizable ceramics. Therefore, it is important to examine the material dependence of ion track formation in terms of amorphization/recrystallization. Ion track formation caused by SHIs is often accompanied by the formation of hillocks (so-called surface ion tracks) [20–35]. Our recent studies revealed that both ion tracks and hillocks are amorphous in the case of amorphizable ceramics (Y3Fe5O12 (YIG)) [36,37], whereas crystalline hillocks are found in the case of non-amorphizable ceramics (CaF2, SrF2, BaF2, and CeO2)[36,38]. Since the surface protrusion is a direct consequence of local melting along the ion path (melting of the ion track region), the observation of crystalline hillocks in non-amorphizable ceramics also provides a strong evidence of recrystallization after melting of the ion track region. It was also found that the hillock diameter always coincides with the diameter of a melt predicted by the thermal spike model for both amorphizable and non-amorphizable ceramics. This means that a hillock diameter value is affected by a melting process, but it remains unchanged after the subsequent recrystallization process. It is likely that a hillock size reflects melting, whereas an ion track size reflects both melting and subsequent recrystallization. Therefore, a comparative analysis of ion tracks and hillocks allows us to elucidate the whole processes of melting and amorphization/recrystallization. Moreover, there must be a variety of hillock and ion track morphologies due to an intricate recrystallization process, which can be the origin of the material dependence of nanostructure formation. We recently proposed a method for precise measurement of a hillock size by transmission electron microscopy (TEM) [36–38]. The method is useful for the direct observation of a hillock side-view. It allows the accurate measurement of hillock dimensions and the identification of hillock crystal structure. In our previous study, we have studied hillocks and ion tracks in non-amorphizable ceramics such as CaF2, SrF2, and BaF2, whereas only one amorphizable ceramic (YIG) has been studied [36,37]. In the present study, we have further studied the relationship between the hillock diameter and ion track diameter for various types of ceramics. First, we show results of the TEM observations for SHI-irradiated amorphizable ceramics such as LiNbO3, ZrSiO4, and Gd3Ga5O12 (GGG) and then for SrTiO3 (STO) and 0.5 wt% niobium-doped STO (Nb-STO), whose hillock formation has not been fully explored. The electrical resistivity of STO increases by more than nine orders of magnitude by doping with 0.5 wt% Nb, whereas its crystal structure remains unaffected by the doping [39]. The effect of Nb doping on its hillock morphology is also investigated in this study. Based on the TEM investigations of both amorphizable and non-amorphizable ceramics, we discuss how the SHI-induced nanostructure formation depends on the intricate recrystallization process. 2. Experiments Thin samples for TEM observations were prepared before irradiation by the following procedure. The original materials were ZrSiO4 (98%) powder (Kojundo Chemical Laboratory Co., Ltd., Saitama, Japan), LiNbO3 single crystals (Onizawa Fine Product Co., Ltd., Ibaraki, Japan), Gd3Ga5O12 (GGG) single crystals (Rare Metallic Co., Ltd., Tokyo, Japan), SrTiO3 (STO) single crystals (Shinkosha Co., Ltd., Kanagawa, Japan), and 0.5 wt% niobium-doped STO (Nb-STO) single crystals (Shinkosha Co., Ltd., Kanagawa, Japan). The original materials were finely ground using an agate mortar and pestle. For the preparation of LiNbO3 specimens, first, 3 mm diameter nickel grids with 2000 lines/inch were coated using 0.5% Neoprene W in toluene (Nisshin EM Co., Ltd., Tokyo, Japan), which works as an adhesive agent, and then the ground LiNbO3 powder was randomly dispersed on the grids. For the preparation of materials other than LiNbO3, the ground samples were dispersed in ethanol by an ultrasonic bath for a few minutes, and then the ethanol was dropped on 3 mm diameter 200 mesh copper grids covered with porous carbon films. The grids were then air-dried at room temperature. The samples on the 32+ grids were subsequently irradiated with 200 MeV Au ions at an oblique incidence angle (45◦ relative to normal direction) at room temperature in a tandem accelerator at JAEA-Tokai (Japan Atomic Energy Agency, Tokai Research and Development Center, Tokai, Japan). The charge state (32+) was chosen to ensure the charge of the incident ions to have the average value of the equilibrium charge. The samples Quantum Beam Sci. 2020, 4, 43 3 of 14 Quantum Beam Sci. 2020, 4, x FOR PEER REVIEW 3 of 15 were irradiated with ions at 1 1011 ions/cm2. The as-irradiated samples were examined using a × JEOLtransmission Ltd., Tokyo, electron Japan) microscope operated (TEM,at 200 kV. Model The 2100F, ion track JEOL size Ltd., was Tokyo, measured Japan) using operated the TEM at images 200 kV. takenThe ion at tracka low size magnification, was measured wherein using clear the TEM line-like images contrasts taken atwere a low expected magnification, to be imaged. wherein On clear the otherline-like hand, contrasts the hillock were expected size was to measured be imaged. using On the the other TEM hand, images the hillocktaken at size a washigh measuredmagnification, using whereinthe TEM a images clear contour taken at of a highhillocks magnification, was expected wherein to be obtained. a clear contour The electronic of hillocks stopping was expected power to (S bee) wasobtained. estimated The electronicusing SRIM-2008 stopping [40,41]. power (Se) was estimated using SRIM-2008 [40,41]. 3. Results Results and and Discussions Discussions 3.1. Dimensions Dimensions of of Hillocks and Ion Tracks in LiNbO3,, ZrSiO ZrSiO4,, and and GGG GGG We havehave observedobserved nanostructures nanostructures created created by by SHI SHI irradiation irradiation in amorphizable in amorphizable ceramics ceramics using using TEM. TEM.Figure Figure1a–c show 1a–c the show bright the field bright images field of images ion tracks of ion in LiNbO tracks3 ,in ZrSiO LiNbO4, and3, ZrSiO Gd3Ga4, and5O12 Gdirradiated3Ga5O12 withirradiated 200 MeV with Au 200 at MeV an oblique Au at an incidence oblique angle.
Load more

Recommended publications
  • Recent Progress in the Membrane Distillation and Impact of Track-Etched Membranes
    polymers Review Recent Progress in the Membrane Distillation and Impact of Track-Etched Membranes Arman B. Yeszhanov 1,2, Ilya V. Korolkov 1,2 , Saule S. Dosmagambetova 1, Maxim V. Zdorovets 1,2,3,* and Olgun Güven 4,* 1 The Institute of Nuclear Physics, Ibragimov Str. 1, Almaty 050032, Kazakhstan; [email protected] (A.B.Y.); [email protected] (I.V.K.); [email protected] (S.S.D.) 2 L.N. Gumilyov Eurasian National University, Satbaev Str. 5, Nur-Sultan 010008, Kazakhstan 3 Ural Federal University, Mira Str. 19, Ekaterinburg 620002, Russia 4 Department of Chemistry, Hacettepe University, Ankara 06800, Turkey * Correspondence: [email protected] (M.V.Z.); [email protected] (O.G.); Tel.: +7-7-01-979-8859 (M.V.Z.); +90-31-2297-7977 (O.G.) Abstract: Membrane distillation (MD) is a rapidly developing field of research and finds applications in desalination of water, purification from nonvolatile substances, and concentration of various solutions. This review presents data from recent studies on the MD process, MD configuration, the type of membranes and membrane hydrophobization. Particular importance has been placed on the methods of hydrophobization and the use of track-etched membranes (TeMs) in the MD process. Hydrophobic TeMs based on poly(ethylene terephthalate) (PET), poly(vinylidene fluoride) (PVDF) and polycarbonate (PC) have been applied in the purification of water from salts and pesticides, as well as in the concentration of low-level liquid radioactive waste (LLLRW). Such membranes are Citation: Yeszhanov, A.B..; Korolkov, characterized by a narrow pore size distribution, precise values of the number of pores per unit area I.V..; Dosmagambetova, S.S..; and narrow thickness.
    [Show full text]
  • And Shape-Controlled Platinum Cones by Ion-Track Etching and Electrodeposition Techniques for Electrocatalytic Applications
    Article Fabrication of Size- and Shape-Controlled Platinum Cones by Ion-Track Etching and Electrodeposition Techniques for Electrocatalytic Applications Yuma Sato 1, Hiroshi Koshikawa 2, Shunya Yamamoto 2, Masaki Sugimoto 2, Shin-ichi Sawada 2 and Tetsuya Yamaki 1,2,* 1 Graduate School of Science and Technology, Gunma University, Kiryu 376-8515, Gunma, Japan; [email protected] 2 Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, Takasaki 370-1292, Gunma, Japan; [email protected] (H.K.); [email protected] (S.Y.); [email protected] (M.S.); [email protected] (S.-i.S.) * Correspondence: [email protected] Abstract: The micro/nanocone structures of noble metals play a critical role as heterogeneous electrocatalysts that provide excellent activity. We successfully fabricated platinum cones by elec- trodeposition using non-penetrated porous membranes as templates. This method involved the preparation of template membranes by the swift-heavy-ion irradiation of commercially available polycarbonate films and subsequent chemical etching in an aqueous NaOH solution. The surface diameter, depth, aspect ratio and cone angle of the resulting conical pores were controlled in the ranges of approximately 70–1500 nm, 0.7–11 µm, 4–12 and 5–13◦, respectively, by varying the etching Citation: Sato, Y.; Koshikawa, H.; conditions, which finally produced size- and shape-controlled platinum cones with nanotips. In Yamamoto, S.; Sugimoto, M.; Sawada, order to demonstrate the electrocatalytic activity, electrochemical measurements were performed for S.-i.; Yamaki, T. Fabrication of Size- and Shape-Controlled Platinum the ethanol oxidation reaction.
    [Show full text]
  • Novel Fission Track Detection for Identification and Characterization of Special Nuclear Materials
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 12-2017 Novel Fission Track Detection for Identification and Characterization of Special Nuclear Materials Jonathan Allen Gill University of Tennessee, Knoxville, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Nuclear Engineering Commons, and the Other Materials Science and Engineering Commons Recommended Citation Gill, Jonathan Allen, "Novel Fission Track Detection for Identification and Characterization of Special Nuclear Materials. " PhD diss., University of Tennessee, 2017. https://trace.tennessee.edu/utk_graddiss/4770 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Jonathan Allen Gill entitled "Novel Fission Track Detection for Identification and Characterization of Special Nuclear Materials." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Nuclear Engineering. Howard L. Hall, Major Professor We have read this dissertation and recommend its acceptance: Thomas T. Meek, Joseph R. Stainback IV, John D. Auxier Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Novel Fission Track Detection for Identification and Characterization of Special Nuclear Materials A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Jonathan Allen Gill December 2017 Copyright © 2017 by Jonathan A.
    [Show full text]
  • Carbon Nanocasting in Ion-Track Etched Polycarbonate Membranes
    Materials Letters 187 (2017) 56–59 Contents lists available at ScienceDirect Materials Letters journal homepage: www.elsevier.com/locate/matlet Carbon nanocasting in ion-track etched polycarbonate membranes ⁎ crossmark Xin Zhaoa,b, Falk Muencha, , Sandra Schaefera, Claudia Fasela, Ulrike Kunza, Sevda Ayatac, Shouxin Liub, Hans-Joachim Kleebea, Wolfgang Ensingera a Technische Universität Darmstadt, Department of Materials and Earth Sciences, Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany b Northeast Forestry University, College of Material Science and Engineering, 150040 Harbin, PR China c Dokuz Eylul University, Science Faculty, Department of Chemistry, Tinaztepe Kampusu, Buca, 35160 Izmir, Turkey ARTICLE INFO ABSTRACT Keywords: We replicate the unique pore structure of ion-track etched polymers with carbon using an organic sol-gel Ion beam technology precursor strategy. First, phenol resin is cross-linked in the membrane pores, followed by selective dissolution Carbon materials of the template matrix and carbonization at a temperature of 550 °C. The potential to create nanomaterials of Template synthesis novel morphology is demonstrated by synthesizing free-standing, interconnected networks composed of aligned Pyrolysis carbon nanowires of defined or modulated diameter. Nanowire networks 1. Introduction These templates can be used to synthesize e.g. parallel arrays [9], networks or hierarchical assemblies [4] of 1D nano-objects. One-dimensional (1D) carbon structures such as nanotubes or Conventional template-assisted carbon deposition routes require nanowires (CNWs) represent one of the most important and frequently high-temperature processes such as chemical vapor deposition, and studied nanomaterial types. Due to their chemical, electrical, optical thus are limited to heat resistant templates such as anodized aluminum and mechanical properties, they can be employed in an exceptionally oxide [10], excluding ion-track etched polymers.
    [Show full text]
  • Multiple Activation of Ion Track Etched Polycarbonate for the Electroless Synthesis of Metal Nanotubes
    Appl Phys A (2011) 105:847–854 DOI 10.1007/s00339-011-6646-z Multiple activation of ion track etched polycarbonate for the electroless synthesis of metal nanotubes F. Muench · M. Oezaslan · T. Seidl · S. Lauterbach · P. Strasser · H.-J. Kleebe · W. Ensinger Received: 15 June 2011 / Accepted: 6 October 2011 / Published online: 4 November 2011 © Springer-Verlag 2011 Abstract In our study, we examined the formation of thin 1 Introduction films of silver nanoparticles on polycarbonate and the in- fluence of the silver loading on the electroless synthesis of In the early 1990s, Martin and coworkers developed several methods for the template-supported synthesis of metallic metal nanotubes. Control of the silver film thickness oc- micro and nanotubes (NTs), focusing on electroless plating curred by consecutive dipping of the polymer template in and ion track etched polycarbonate [1–3]. Ion track etched tin(II) and silver(I) solutions. The deposition progress was polymer templates contain stochastically distributed chan- studied using UV-Vis spectroscopy. The reaction mecha- nels whose density, diameter, and shape can be substantially nism relies on the adsorption of reactive ions on the poly- varied by the production conditions [4–6]. Wires and tubes mer template as well as on the silver nanoparticles. The are obtained by depositing metals in these channels [7–10]. initial catalytic activity of silver-covered ion track etched These virtually one-dimensional nanostructures have been effectively implemented in relevant fields such as nanoelec- polycarbonate is an important governing factor for the elec- trochemistry [3], field emission [7], selective chemical trans- troless synthesis of metal nanotubes with desired thickness port [8] and flow-through [9], or fuel cell [10] catalysis.
    [Show full text]
  • Ion-Track Technology Based Synthesis and Characterization of Gold and Gold Alloys Nanowires and Nanocones
    Ion-track technology based synthesis and characterization of gold and gold alloys nanowires and nanocones Vom Fachbereich Material- und Geowissenschaften der Technischen Universität Darmstadt zur Erklärung des akademischen Grades eines Doktors der Naturwissenschaften (Dr. rer. nat.) genehmigte Dissertation von Dipl. Ing. M.Sc. Loïc Burr aus Colmar (Frankreich) June 2016 - Darmstadt – D17 Ion-track technology based synthesis and characterization of gold and gold alloys nanowires and nanocones genehmigte Disseration von Dipl. Ing. M.Sc. Loïc Burr aus Colmar (Frankreich) 1. Gutachten: Prof. Dr. Christina Trautmann 2. Gutachten: Prof. Dr. Ralph Krupke Tag der Einreichung: 21.04.2016 Tag der mündlichen Prüfung: 21.04.2016 Darmstadt – 2016 D17 II | P a g e The work described in this thesis was carried out between November 2012 and June 2013 under the supervision of Prof. Dr. Trautmann at the Materials Research group of the GSI Helmholtz Centre for Heavy Ion Reseach, Plackstraße 1, D- 64291 Darmstadt, Germany Top cover image: colorized SEM image of Au nanowires standing on their Au backelectrode fabricated by electrodeposition in etched ion track templates as presented in this thesis Back cover image: modified SEM image of Au nanocones with their caps overlaying a nanocone array III | P a g e Erklärung zur Dissertation Hiermit versichere ich, die vorliegende Dissertation ohne Hilfe Dritter und nur mit den angegebenen Quellen und Hilfsmitteln angefertigt zu haben. Alle Stellen, die aus den Quellen entnommen wurden, sind als solche kenntlich gemacht worden. Diese Arbeit hat in dieser oder ähnlicher Form noch keiner Prüfungsbehörde vorgelegen. Darmstadt, den 19.04.2016 _________________________________ (Loïc Burr) Loïc Burr Ion-track technology based synthesis and characterization of gold and gold alloys nanowires and nanocones PhD Thesis, Technische Universität Darmstadt, Darmstadt, Germany URN: urn:nbn:de:tuda-tuprints-55410 URI: http://tuprints.ulb.tu-darmstadt.de/id/eprint/5541 Copyright © 2016 by L.
    [Show full text]
  • Fullerene Irradiation Leading to Track Formation Enclosing Nitrogen Bubbles in Gan Material J.G
    Fullerene irradiation leading to track formation enclosing nitrogen bubbles in GaN material J.G. Mattei, M. Sall, F. Moisy, A. Ribet, E. Balanzat, C. Grygiel, I. Monnet To cite this version: J.G. Mattei, M. Sall, F. Moisy, A. Ribet, E. Balanzat, et al.. Fullerene irradiation leading to track formation enclosing nitrogen bubbles in GaN material. Materialia, Elsevier, 2021, 15, pp.100987. 10.1016/j.mtla.2020.100987. hal-03162888v2 HAL Id: hal-03162888 https://hal.archives-ouvertes.fr/hal-03162888v2 Submitted on 2 Apr 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Fullerene irradiation leading to track formation enclosing nitrogen bubbles in GaN material JG Mattei, M. Sall, F. Moisy, A. Ribet, E. Balanzat, C. Grygiel, and I. Monnet* CIMAP, CEA-CNRS-ENSICAEN-Normandie Université BP5133 F-14070 Caen cedex5 France. * Corresponding author: [email protected] Abstract Gallium nitride was irradiated with fullerene projectiles having an electronic stopping power above the threshold required to promote ion track formation. The structural and chemical changes induced by fullerene irradiation were studied through Transmission Electron Microscopy (TEM). High resolution TEM inquiries were performed to identify the structural order along the ion tracks and the strain induced in the lattice neighboring the ion tracks.
    [Show full text]
  • Pro Sto A02 Msds 002 Msds Pi Membrane
    MATERIAL SAFETY DATA SHEET MSDS003 - MSDS - Version 06 POLYIMIDE (PI) Date 01/06/21 TRACK-ETCHED MEMBRANE Page 1/6 ION TRACK TECHNOLOGY SECTION 1 : COMPANY INFORMATION ............................................................................................................. 2 MANUFACTURER / DISTRIBUTOR 2 MSDS MANAGER 2 SECTION 2 : COMPOSITION / INFORMATION ON INGREDIENTS ................................................................. 2 SECTION 3 : HAZARD IDENTIFICATION / EMERGENCY OVERVIEW .......................................................... 2 APPEARANCE 2 CLASSIFICATION 2 ADVERSE HUMAN HEALTH EFFECTS 2 TARGET ORGANS 2 MEDICAL CONDITIONS AGGRAVATED BY EXPOSURE 2 SECTION 4 : FIRST AID MEASURES .................................................................................................................... 3 CONTACT WITH EYES 3 INGESTION 3 INHALATION 3 SKIN CONTACT 3 SECTION 5 : FIRE FIGHTING MEASURES ........................................................................................................... 3 SUITABLE EXTINGUISHING MEDIA 3 SPECIFIC HAZARDS WITH REGARD TO FIRE-FIGHTING MEASURES 3 SPECIFIC FIRE-FIGHTING MEASURES 3 SPECIFIC FIRE-FIGHTING MEASURES 3 SECTION 6 : ACCIDENTAL RELEASE MEASURES ........................................................................................... 4 PERSONAL PRECAUTIONS 4 SMALL AND LARGE SPILLS 4 ADVERSE ENVIRONMENTAL AND PHYSIOCHEMICAL EFFECTS 4 CLEAN UP MEASURES 4 SECTION 7 : HANDLING AND STORAGE ..........................................................................................................
    [Show full text]
  • Cooperative Effect of Electronic and Nuclear Stopping on Ion Irradiation
    Cooperative effect of electronic and nuclear stopping on ion irradiation damage in silica M Backman1;2, F Djurabekova2, O H Pakarinen2, K Nordlund2, Y Zhang3;1, M Toulemonde4 and W J Weber1;3 1 Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA 2 Helsinki Institute of Physics and Department of Physics, P.O. Box 43, FI-00014 University of Helsinki, Finland 3 Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA 4 CIMAP-CEA-CNRS-ENSICAEN-University of Caen, F-14070 Caen Cedex 5, France E-mail: [email protected] Abstract. Radiation damage by ions is conventionally believed to be produced either by displacement cascades or electronic energy deposition acting separately. However, there is a range of ion energies where both processes are significant and could contribute to irradiation damage. The combination of two computational methods, namely binary collision approximation and molecular dynamics, the latter with input from the inelastic thermal spike model, makes it possible to examine the simultaneous contribution of both mechanisms of energy deposition on the structural damage in the irradiated structure. We study the effect in amorphous SiO2 irradiated by Au ions with energies ranging between 0.6 and 76.5 MeV. We find that in the intermediate energy regime, there is a synergistic effect of local heating due to electronic excitations in enhancing the displacement cascade damage. PACS numbers: 61.80.Jh, 61.43.Bn, 61.43.Fs Cooperative effect of electronic and nuclear stopping 2 1. Introduction Ion irradiation of solids is a topic that is studied both as a tool for materials modification and as a source of damage to materials in, for instance, nuclear reactors.
    [Show full text]
  • NSF-EC Workshop on Nanomaterials and Nanotechnology Summary Report
    NSF-EC Nanomaterials Workshop 2002 NSF-EC Workshop on Nanomaterials and Nanotechnology Summary Report I. Workshop Overview The NSF-EC workshop on nanomaterials and nanotechnology was held in Boston, Massachusetts on December 5-7 2002. Both the US and the EC realize the importance of a globally trained technical workforce. A focused effort to enhance interactions between the U.S. and E.C. in scientific research is one important way to create a culture where international cooperation is the rule rather than the exception. This workshop was developed to provide important feedback to NSF and EC on two issues: I) The most critical and timely issues facing those investigators developing new nanomaterials and technologies related to those materials and II) The best practices for catalyzing cooperative research in the emerging area of nanomaterials. Appendix A provides a list of attendees while Appendix B gives the program and talk titles. Recommendations for important topics and challenges in nanomaterials research were arrived at by discussions in breakout groups in each of the three topical theme areas of the work. These discussions were preceded by brief talks from each of the participants. The common themes found in this discussion: • An increased focus on developing materials which have multifunctional capabilities. Nanoparticles that can both sense and treat disease for example, devices that leverage both the optical and electronic properties of nanoparticles assemblies, or functional coatings whose biodegradation can be triggered after a certain time. • Recognition of the importance that the environmental impact of nanomaterials in developing sustainable nanotechnologies. Very little is known about how nanomaterials interact with animals and the larger environment.
    [Show full text]
  • Effect of Orientation on Ion Track Formation in Apatite and Zircon
    American Mineralogist, Volume 99, pages 1127–1132, 2014 Effect of orientation on ion track formation in apatite and zircon Weixing Li1,*,†, Patrick kLuth2, DanieL SchaurieS2, MatiaS D. roDriguez2, Maik Lang1, Fuxiang zhang1, MaxiM zDorovetS3, chriStina trautMann4 anD roDney c. eWing1,5,† 1Department of Earth & Environmental Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005, U.S.A. 2Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200, Australia 3Institute of Nuclear Physics, and The L.N. Gumilyov Eurasian National University, Astana, 010008, Kazakhstan 4GSI Helmholtz Centre for Heavy Ion Research, 64291 Darmstadt, and Technische Universität Darmstadt, Germany 5Departments of Materials Science & Engineering, and Nuclear Engineering & Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2104, U.S.A. aBStract revealed by chemical etching, because, until now, unetched, latent FTs could not be examined analyti- cally at the atomic-scale. The major challenge to such an analysis has been the random orientation of FTs and their extremely small diameters. Here we use high-energy ions (2.2 GeV Au or 80 MeV transmission electron microscopy (TEM) of single tracks and small-angle X-ray scattering (SAXS) for millions of tracks, a precise picture of track morphology as a function of orientation is obtained. High-resolution analysis reveals that orientation affects the shape of tracks in apatite and zircon through the preferential creation of damage along directions with highest atomic density. However, track radius does not depend on orientation, contradicting previous reports. Independent of track orientation, track radii, as measured at each point along the entire length of 80 MeV Xe ion tracks in apatite, can be understood using the thermal spike model of Szenes.
    [Show full text]
  • MIAMI UNIVERSITY the Graduate School Certificate for Approving The
    MIAMI UNIVERSITY The Graduate School Certificate for Approving the Dissertation We hereby approve the Dissertation of Aleksey N. Pisarenko Candidate for the Degree: Doctor of Philosophy _____________________________________ Director Dr. Gilbert E. Pacey _____________________________________ Director (Committee Chairperson) Dr. Gilbert Gordon _____________________________________ Reader Dr. Richard T. Taylor _____________________________________ Reader Dr. Michael W. Crowder _____________________________________ Graduate School Representative Dr. Luis A. Actis Abstract ANALYTICAL MEASUREMENTS AND PREDICTIONS OF PERCHLORATE ION CONCENTRATION IN SODIUM HYPOCHLORITE SOLUTIONS AND DRINKING WATER: KINETICS OF PERCHLORATE ION FORMATION AND EFFECTS OF ASSOCIATED CONTAMINANTS by Aleksey N. Pisarenko The dissertation consists of six chapters that summarize the investigation of factors impacting perchlorate ion formation in sodium hypochlorite solutions and the development of a predictive model for perchlorate ion formation. There are also two appendices detailing the synthesis and applications of nanomaterials for designing sensors. Chapter 1 gives a brief history of perchlorate ion as an emerging contaminant. A background on the occurrence, toxicology, and regulatory actions is provided. Chapter 2 focuses on the analytical methods that were developed and validated for analysis of perchlorate, bromate, chlorate, hypochlorite, and chlorite ions in various hypochlorite ion solutions. Comparison of a LC-MS/MS method and an iodometric titration method is provided. The chapter also details sample preparation methods, such as the use of malonic acid to stop formation of perchlorate ion. Chapter 3 details the experimental matrix to identify factors that impact perchlorate ion formation. Effects of different contaminants were investigated at elevated temperatures. Chapter 4 provides a detailed investigation of the effects of concentration of hypochlorite and chlorate ions, ionic strength, and temperature.
    [Show full text]